xref: /freebsd/lib/libc/stdio/fgetws.3 (revision 8ddb146abcdf061be9f2c0db7e391697dafad85c)
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32.\"     @(#)fgets.3	8.1 (Berkeley) 6/4/93
33.\" FreeBSD: src/lib/libc/stdio/fgets.3,v 1.16 2002/05/31 05:01:17 archie Exp
34.\" $FreeBSD$
35.\"
36.Dd August 6, 2002
37.Dt FGETWS 3
38.Os
39.Sh NAME
40.Nm fgetws
41.Nd get a line of wide characters from a stream
42.Sh LIBRARY
43.Lb libc
44.Sh SYNOPSIS
45.In stdio.h
46.In wchar.h
47.Ft "wchar_t *"
48.Fn fgetws "wchar_t * restrict ws" "int n" "FILE * restrict fp"
49.Sh DESCRIPTION
50The
51.Fn fgetws
52function
53reads at most one less than the number of characters specified by
54.Fa n
55from the given
56.Fa fp
57and stores them in the wide character string
58.Fa ws .
59Reading stops when a newline character is found,
60at end-of-file or error.
61The newline, if any, is retained.
62If any characters are read and there is no error, a
63.Ql \e0
64character is appended to end the string.
65.Sh RETURN VALUES
66Upon successful completion,
67.Fn fgetws
68returns
69.Fa ws .
70If end-of-file occurs before any characters are read,
71.Fn fgetws
72returns
73.Dv NULL
74and the buffer contents remain unchanged.
75If an error occurs,
76.Fn fgetws
77returns
78.Dv NULL
79and the buffer contents are indeterminate.
80The
81.Fn fgetws
82function
83does not distinguish between end-of-file and error, and callers must use
84.Xr feof 3
85and
86.Xr ferror 3
87to determine which occurred.
88.Sh ERRORS
89The
90.Fn fgetws
91function will fail if:
92.Bl -tag -width Er
93.It Bq Er EBADF
94The given
95.Fa fp
96argument is not a readable stream.
97.It Bq Er EILSEQ
98The data obtained from the input stream does not form a valid
99multibyte character.
100.El
101.Pp
102The function
103.Fn fgetws
104may also fail and set
105.Va errno
106for any of the errors specified for the routines
107.Xr fflush 3 ,
108.Xr fstat 2 ,
109.Xr read 2 ,
110or
111.Xr malloc 3 .
112.Sh SEE ALSO
113.Xr feof 3 ,
114.Xr ferror 3 ,
115.Xr fgets 3
116.Sh STANDARDS
117The
118.Fn fgetws
119function
120conforms to
121.St -p1003.1-2001 .
122